Chemical characterisation by WD-XRF and XRD of silicon carbide-based grinding tools

摘要

This paper addresses the chemical characterisation of silicon carbide-based grinding tools. These are among the most widely used grinding tools in the ceramic sector, and instruments are required that enable the grinding tool quality to be controlled, despite the considerable complexity involved in determining grinding tool chemical composition. They contain components of quite different nature, ranging from the silicon carbide abrasive to the resin binder. To develop the analysis method, grinding tools containing silicon carbidewith different grain sizes were selected from different tile polishing stages. To develop the grinding tool characterisation method, the different measurement process steps were studied, from sample preparation, in which different milling methods (each appropriate for the relevant type of test) were used, to the optimisation of the determination of grinding tool components by spectroscopic and elemental analyses. For each technique, different particle sizes were used according to their needs. For elemental analysis, a sample below 150 μm was used, while for the rest of the determinations a sample below 60 μm was used. After milling, the crystalline phases were characterised by X-ray powder diffraction and quantified using the Rietvel method. The different forms of carbon (organic carbon from the resin, inorganic carbon from the carbonates and carbon from the silicon carbide) were analysed using a series of elemental analyses. The other elements (Si, Al, Fe, Ca, Mg, Na, K, Ti, Mn, P and Cl) were determined by wavelength-dispersive X-ray fluorescence spectrometry, preparing the sample in the form of pressed pellets and fused beads. The chemical characterisation method developed was validated with mixtures of referencematerials, as there are no reference materials of grinding tools available. This method can be used for quality control of silicon carbide-based grinding tools.